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Re:Bike frame stiffness: Why it matters and all you need to ... by max_k on Wednesday December 21, 2022 @04:13PM (#34086471)
A year ago, my titanium fork broke (while driving rather slowly on good tarmac, photo here https://twitter.com/dothebart/status/1486765955254530051), and the titanium frame got a few cracks as well. My motto "the last bike I'll ever buy" collided with reality. Fortunately, I got away with just a few scratches - just a minute later, I would have been at 60+ kph downhill. My new bike has a steel frame. I love it, but titanium was more flexible and more comfortable. And of course titanium is nerdier! :-)
Re:Bike frame stiffness: Why it matters and all you need to ... by kasey_junk on Wednesday December 21, 2022 @04:41PM (#34086777)
Did the manufacturer provide an explanation? A sheer (which that looks like) should be near impossible on any properly manufactured bicycle under normal usage.
Re:Bike frame stiffness: Why it matters and all you need to ... by max_k on Wednesday December 21, 2022 @04:56PM (#34086910)
No. I got a full refund, though. Most importantly, I'm so extremely happy I'm still alive, I don't care about anything else.
Re:Bike frame stiffness: Why it matters and all you need to ... by kasey_junk on Wednesday December 21, 2022 @09:42PM (#34089057)
I wouldn’t view that as an indictment of a particular material.

That’s like first generation carbon failure and those went away 20 years ago. I’d blame the manufacturer specifically in that case because it’s both catastrophic & unexpected.

Re:Bike frame stiffness: Why it matters and all you need to ... by robin_reala on Thursday December 22, 2022 @12:41AM (#34090221)
Sudden memories of early http://www.bustedcarbon.com/
Re:Bike frame stiffness: Why it matters and all you need to ... by jupp0r on Wednesday December 21, 2022 @04:28PM (#34086631)
Glad you're ok. I wish the anti helmet crowd from the Netherlands from a different thread 2 weeks ago would read this.
Re:Bike frame stiffness: Why it matters and all you need to ... by Xylakant on Wednesday December 21, 2022 @04:45PM (#34086820)
The “anti helmet crowd” wouldn’t have any issue reading be this. Wearing helmets when you’re on a sports bike is very common in the Netherlands. It’s just not common on Dutch commuters cycles, but then again, these do not have this failure mode. Sports bikes in general have much less margin for failure, and thus fail more often and catastrophic than a solid steel bike.
Re:Bike frame stiffness: Why it matters and all you need to ... by jupp0r on Wednesday December 21, 2022 @05:01PM (#34086954)
Right, all commuter bikes are made of solid steel and steel bikes never break. Got it.
Re:Bike frame stiffness: Why it matters and all you need to ... by Xylakant on Wednesday December 21, 2022 @05:37PM (#34087327)
Typical Dutch commuter bikes are made of steel. And yes, steel breaks, but the failure mode of a solid steel fork is much much different from a titanium, aluminum or carbon fork. They bend, crack and at some point break, but they’ll typically not snap like this because steel is much less brittle than any of those materials.

Also, speed matters. Going 15 or 50 when the thing breaks makes a difference.

Re:Bike frame stiffness: Why it matters and all you need to ... by digitalscribe on Wednesday December 21, 2022 @11:56PM (#34089978)
> Also, speed matters. Going 15 or 50 when the thing breaks makes a difference.

Isnt this an argument that helmets are more important for passenger vehicles? After all, car accidents cause about 10x more head trauma in the usa.

Re:Bike frame stiffness: Why it matters and all you need to ... by toast0 on Thursday December 22, 2022 @12:25AM (#34090135)
Passenger vehicles from this century come with airbags that significantly reduce head trauma. Three point seatbelts have been mandatory in all seating positions for longer, IIRC, and significantly reduce the likelyhood of head vs pavement collisions.

But, if absolute safety is paramount, you do want a five point harness, flameresistant coveralls, neck support, and a helmet, sure.

Re:Bike frame stiffness: Why it matters and all you need to ... by prmoustache on Thursday December 22, 2022 @02:17AM (#34090728)
You are very unlikely to crash at 15-20kph and even less likely to hit your head at such speed in a very upright position.

In fact the odds aren't bigger than when running. Do you think runners should wear helmets?

I chose to wear or not my helmet depending on the conditions. Running errands nearby on my girlfriend's lady bike? I don't use it. Riding on mostly separated bicycle paths at my girlfriend's slow pace, same. Riding 3h on the roads or trails on my road and mountain bikes, I wear it.

Re:Bike frame stiffness: Why it matters and all you need to ... by ajuc on Thursday December 22, 2022 @03:38AM (#34091150)
* * *
Re:Bike frame stiffness: Why it matters and all you need to ... by kqr on Wednesday December 21, 2022 @05:08PM (#34087025)
I don't think any "anti helmet crowd" would claim that helmets never ever help. Just that it's rare enough that it may not be worth the inconvenience.

After all, are you strapping on a helmet while you're out walking, or driving a car? Sometimes, very rarely, that could be what saves your life.

Re:Bike frame stiffness: Why it matters and all you need to ... by midoridensha on Wednesday December 21, 2022 @07:59PM (#34088408)
I don't know about you, but I can't walk at 15kph+, so the amount of crash energy my head would experience while walking is quite low.
Re:Bike frame stiffness: Why it matters and all you need to ... by SECProto on Thursday December 22, 2022 @12:10AM (#34090062)
15-20 km/h is a fairly common pace in running races (2:05 to 2:50 marathon pace), no helmets are worn there.
Re:Bike frame stiffness: Why it matters and all you need to ... by midoridensha on Thursday December 22, 2022 @12:38AM (#34090205)
When you fall while running, you don't have a mechanical contraption limiting your movement. The nature of riding a bicycle (or motorcycle) makes it much more likely you'll hit your head. People also don't fall as much while running as they do when riding: it's easy to hit a crack in the pavement and lose control on a bike.
Re:Bike frame stiffness: Why it matters and all you need to ... by haspok on Thursday December 22, 2022 @03:29AM (#34091101)
> People also don't fall as much while running as they do when riding

Says who?

Just a couple of days ago I had a runner get past me while I was walking on the street, 2 seconds later she hit a bump on the pavement with her foot and fell down hard (she even made a loud splash sound as she hit the ground). No, she didn't have a helmet. Should she have?

At the end of the day, people should be walking around in full steel plate armour, for protection and safety. Or even better, not walking around at all. Bicycles should be banned!

> it's easy to hit a crack in the pavement and lose control on a bike.

No, its not. The person who says this probably hadn't ridden a bicycle in their life, or if they have, not often and not recently.

Bicycle wheels are EXCELLENT at getting over cracks, bumps, ditches, holes, whatever - as long as the attack angle is as close to 90 degrees as possible. It is the riders responsibility to make sure that is the case. Wider tires also help, lower pressures too... and high speeds, counterintuitively.

Of course, if you are afraid of falling or uncertain of your skills on the bike, wear a helmet by all means. Just don't think that it is "normal" and all riders are like that.

Re:Bike frame stiffness: Why it matters and all you need to ... by midoridensha on Thursday December 22, 2022 @04:32AM (#34091530)
>2 seconds later she hit a bump on the pavement with her foot and fell down hard (she even made a loud splash sound as she hit the ground). No, she didn't have a helmet. Should she have?

Did she hit her head? Humans are hardwired by millions of years of evolution to protect themselves in falls using their arms and hands; they generally handle falls very well. Humans have not evolved to handle riding bikes, and using your hands to protect your head in falls isn't instinctive there like it is while running or walking.

>No, its not. The person who says this probably hadn't ridden a bicycle in their life, or if they have, not often and not recently.

This is just stupid and argumentative. Road surfaces are frequently bad and people make mistakes.

>Of course, if you are afraid of falling or uncertain of your skills on the bike, wear a helmet by all means.

Yes, because I'm sure you're such a perfect rider who never makes a mistake.

Re:Bike frame stiffness: Why it matters and all you need to ... by kqr on Thursday December 22, 2022 @01:31AM (#34090476)
The helmet protects you from other things moving at you, not just you moving at other things.
Re:Bike frame stiffness: Why it matters and all you need to ... by prmoustache on Thursday December 22, 2022 @02:20AM (#34090746)
They may help but they aren't really designed for that.

Helmets are designed to limit head injuries when you bang your head on the ground mostly. If you get mauled by a truck or a suv it is unlikely to help much although it will still help if you bang and rebound on it.

Re:Bike frame stiffness: Why it matters and all you need to ... by fsckboy on Thursday December 22, 2022 @02:41AM (#34090864)
> After all, are you strapping on a helmet while you're out walking, or driving a car?

you are much more likely to fall from a bicycle than while walking or getting in or out of a car. For people who are at risk from falling while walking, yes, precautions are taken that they not fall or hit their heads (or hips), it's quite dangerous.

Re:Bike frame stiffness: Why it matters and all you need to ... by kqr on Thursday December 22, 2022 @03:44AM (#34091182)
Your argument is that the additional protection of a helmet is not worth the additional inconvenience for you when you are walking or driving.

That's the exact same argument the anti-helmet crowd is making of cycling.

In order for your argument to work, you have to either provide a quantitative basis for why your tradeoff totally is worth it and the other is not, or you have to come up with a qualitatively different argument.

Re:Bike frame stiffness: Why it matters and all you need to ... by fsckboy on Thursday December 22, 2022 @06:24PM (#34100347)
I'm not making an argument, neither about helmets for pedestrians nor cyclists. I'm pointing out that others are not focusing on the right metrics to make their arguments, or are providing spurious commentary.

> the additional protection of a helmet is not worth the additional inconvenience

I actually pointed out that protection of a helmet for pedestrians is called for as standard practice (by others, not by me)

Re:Bike frame stiffness: Why it matters and all you need to ... by max_k on Wednesday December 21, 2022 @05:10PM (#34087057)
Oh, bike helmets. I missed that thread, and I don't want to start yet another endless internet discussion about helmets, but let me point out one thing: the helmet I did wear likely wouldn't have saved my life, had the fork breakage happened one minute later.
Re:Bike frame stiffness: Why it matters and all you need to ... by edejong on Wednesday December 21, 2022 @08:19PM (#34088543)
I’m 100% Dutch. I ride road bikes and commuter bikes. I’ve never in my life seen a steel commuter bike break like that. They rust, they bent and they scratch, but they won’t break. Or maybe if you buy a very iffy brand?

As a road cyclist I go 30-50 km/h with a helmet. And as a commuter I’ll keep a moderate 20 km/h without a helmet. Big difference in terms of kinetic energy.

Re:Bike frame stiffness: Why it matters and all you need to ... by fsckboy on Thursday December 22, 2022 @02:38AM (#34090846)
I'm pretty sure the primary kinetic energy you need to worry about in a fall is the vertical drop.
Re:Bike frame stiffness: Why it matters and all you need to ... by discreteevent on Thursday December 22, 2022 @04:07AM (#34091309)
In the worst case the speed your head would hit the ground at would be about 15 km/h.
Re:Bike frame stiffness: Why it matters and all you need to ... by fsckboy on Thursday December 22, 2022 @03:15PM (#34098046)
it's not really a theoretical problem, people actually die or experience brain damage from falling over while standing still; we know a fall of that distance is dangerous. Helmets reduce the impact and save lives and brains. The only real question is the frequency of the falls taking place from bicycles.
Re:Bike frame stiffness: Why it matters and all you need to ... by newaccount74 on Thursday December 22, 2022 @07:37AM (#34092695)
You are much more likely to catch your fall with your hands when you have an accident with your city bike vs a road bike.

Biking at less than 25km/h just isn't that dangerous (unless a car hits you)

Re:Bike frame stiffness: Why it matters and all you need to ... by fsckboy on Thursday December 22, 2022 @03:19PM (#34098089)
being more likely to catch your fall needs to be computed against how likely the falling is, and how likely injury is. This just confuses things, much easier to look at how many injuries occur.
Re:Bike frame stiffness: Why it matters and all you need to ... by ralfd on Wednesday December 21, 2022 @04:28PM (#34086633)
I thought titan would keep good for a life time?
Re:Bike frame stiffness: Why it matters and all you need to ... by max_k on Wednesday December 21, 2022 @05:01PM (#34086955)
... yes, that's what they say about titanium, why I decided to pay the price, but turns out it's not true.
Re:Bike frame stiffness: Why it matters and all you need to ... by speed_spread on Wednesday December 21, 2022 @08:22PM (#34088566)
The metal, yes. What's at stake here seems to be the welding, which is the tricky part with titanium.
Re:Bike frame stiffness: Why it matters and all you need to ... by giuliomagnifico on Wednesday December 21, 2022 @05:14PM (#34087100)
Woaa horror story, what a luck that you didn’t get hurt!

Anyway it’s weird because it doesn’t look broken on a weld, very rare situation, titanium should last forever.

Re:Bike frame stiffness: Why it matters and all you need to ... by 70rd on Wednesday December 21, 2022 @11:17PM (#34089733)
Yeah, I'm kind of flabbergasted to be honest, total failures like that are rare for metal tubing.
Re:Bike frame stiffness: Why it matters and all you need to ... by steelframe on Wednesday December 21, 2022 @08:00PM (#34088410)
> my titanium fork broke

Yikes! Fork failure is the stuff of nightmares. I'm glad you're okay.

Among the participants of a local riding club in my area, I've met two people with custom titanium frame builds who told me that their frames cracked within a few years of use.

Re:Bike frame stiffness: Why it matters and all you need to ... by liotier on Wednesday December 21, 2022 @08:16PM (#34088526)
> Yikes! Fork failure is the stuff of nightmares

Still have nightmares about a fork that, during a mountain bike descent 30 years ago, started oscillating increasingly until it bent and locked the wheel perpendicular to my vector - and my buddy still has dreams of me acting Superman along his ride, for a few short instants...

Re:Bike frame stiffness: Why it matters and all you need to ... by galangalalgol on Thursday December 22, 2022 @12:26AM (#34090138)
Titanium can have problems with oils I've been told. Seeping into crystal defects and propagating. Typically I've been told they use polymer coatings to prevent the ingress. But with scratches and lubricants I think this would be much more common if it was a real thing.

I've always thought a spring bronze/brass frame would be fun. Even better modulus of elasticity, but the strength to weight is much worse.

Also keep waiting to see flash bainite frames.

Re:Bike frame stiffness: Why it matters and all you need to ... by xcskier56 on Wednesday December 21, 2022 @08:42PM (#34088696)
One of my coaches in college raced for a pro/semi-pro team. Their first race of the season was on new/pre-production bikes straight from one of the major manufacturers. 3, I repeat, 3 steer tubes broke in that 1 race. It was a really rugged race, but needless to say the manufacturer had to scramble to fix the forks before going to production.

One guy was going over railroad tracks and his handlebars just came off. Not what you want in the middle of a cat-1/pro peloton.

Re:Bike frame stiffness: Why it matters and all you need to ... by WalterBright on Thursday December 22, 2022 @02:38AM (#34090845)
That's what happens when one tries to shave grams off of the weight.
Re:Bike frame stiffness: Why it matters and all you need to ... by analog31 on Wednesday December 21, 2022 @11:13PM (#34089720)
I had one of the fork ends break off a steel fork. Fortunately I was going at less than a walking pace, navigating out of a store parking lot. I was 2 miles from home, and just walked the bike while planning its replacement.

It was a break that I would have noticed much sooner, had I regularly inspected it, because the other side was half broken off.

The funny thing is, I play in a band, and when I told my story that night, 3 guys in the band offered to weld it.

Re:Bike frame stiffness: Why it matters and all you need to ... by kazinator on Thursday December 22, 2022 @01:27AM (#34090454)
I'd get the drummer to put together the rig which holds the parts in place, bass player to make the crucial spot welds and then the lead guitarist to go ape shit with the rest, while the singer goes whoo yeah!
Re:Bike frame stiffness: Why it matters and all you need to ... by bambax on Thursday December 22, 2022 @04:18AM (#34091388)
OMG the image is terrifying! Glad you were ok...